A shopkeeper purchases birdfeeders for $10 each and sells them for $18 each. If the cost of the feeders increases by 50% for two months in a row, what is the smallest percent increase the shopkeeper can apply to the selling price in order to avoid selling at a loss?

If the cost increases by 50% for two consecutive months, it becomes (1+0.5)*(1+0.5)*20 = 22.5. Then, in order to avoid a loss, the selling cost must be equal to 22.5. Then, the percent increase in the selling cost should be [(22.5-18)/18]*100 = 25%

A shopkeeper purchases birdfeeders for $10 each and sells them for $18 each. If the cost of the feeders increases by 50% for two months in a row, what is the smallest percent increase the shopkeeper can apply to the selling price in order to avoid selling at a loss?

A shopkeeper purchases birdfeeders for $10 each and sells them for $18 each. If the cost of the feeders increases by 50% for two months in a row, what is the smallest percent increase the shopkeeper can apply to the selling price in order to avoid selling at a loss?

No. The stem says just this: 50% the first-month increase, then the second month a more 50% upon the first increase. Pretty straight.

Regards

i know what the stem means; problem is that the asnwer should be considered the percent increase in one month or 2?

2.

Moreover, the question implies that you do have a threshold over which you must have a gain and not a loss. So, if the shop sells at $18 and in the first month have the increase at $15 , if being this way you have a loss. No matter what.

\(\frac{15-18}{18} = \frac{-3}{18}\) not possible

Considering the 2 you do have a certain amount (in this case 22.5) minus 18, you can obtain the % for not having a loss but a gain.